Another strange error message I received when I went on to open a Windows Store app – This app can’t open while File Explorer is running with administrator privileges. Restart File Explorer normally and try again. Now I hadn’t intentionally run File Explorer as an administrator, so why did this happen – and what could I do?

Read: Why does Windows File Explorer not run as administrator.

This app can’t open – File Explorer

Windows Store apps inherit that administrative access tokens of the Explorer process that launch it. If Explorer is indeed running as an elevated process, this will violate the sandboxed environment provided by the AppContainer integrity level.

Well here are a few points you may want to consider:

Check if this happens for a particular app or for all your apps.
Restart File Explorer. Press Ctrl+Shift+Esc to open the Task Manager, locate the Windows Explorer process, right-click and select Restart, See if this helps.
Restart your Windows computer and see if this problem goes away. A restart usually solves many such random issues.
Run the App Troubleshooter and let it fix and problems if they are found.
If you are using a local account, sign-in with your Microsoft Account and see what happens. Change your user account and check
If you are using a proxy connection, then open Internet Options > Connections > LAN settings > Uncheck Use a proxy server for your LAN > Select Automatically detect settings.

I hope something here helps you.

Similar ‘This app can’t open’ errors for: